When brightness rises and falls slightly from frame to frame and the picture flickers, even it out using the average brightness of several frames.
AI clips whose brightness and texture waver frame to frame, time-lapses, and live-action sources shot under fluorescent or LED lights.
Generative models draw brightness and texture slightly differently on each frame, so the picture can even flicker as if it were breathing. In ffmpeg, use something like deflicker=size=10:mode=pm, which levels the brightness using the average of several frames before and after, and in Resolve Studio, use the Deflicker effect. A larger size evens things out more, but it also erases real brightness changes like the moment a light switches on, so don't apply it to those cuts. It is a filter that only fixes brightness, so for flicker where the texture changes, use it together with light temporal denoising (see Denoise).
Smooth frame-to-frame brightness flicker in a generated clip by averaging the luminance of 10 neighboring frames: ffmpeg -i in.mp4 -vf deflicker=size=10:mode=pm -c:a copy out.mp4. Skip shots where a light truly switches on or off, and add a light hqdn3d denoise if the texture still shimmers.
enigmatic_e — Remove AI video flicker using DaVinci Resolve Studio